try with https://forums.mydigitallife.net/threads/slp-marker-file-update-utilities.9055/page-15#post-478696
make a pure DOS bootable USB stick unpack official EN_SB87_89_3A08.zip to the stick replace official PB3G3A08.BIN with modified one boot to pure DOS and run flash.bat ( or type and run phlash16.exe PB3G3A08.bin /x /s )
Nevermid I booted off USB finally... My server only can hold upto 8 boot drives so I had to disable 1 to boot from USB tehn I flashed Bios and It is confirmed Working at lest!!!